Functions and Their Graphs 1.1 Lines in the Plane
The Slope of a Line The slope of a nonvertical line represents the number of units the line rises or falls vertically for each unit of horizontal change from left to right.
Example 1: Finding Slope (a) (-2, 0) and (3, 1) (b) (-1, 2) and (2, 2) (c) (0, 4) and (1, -1)
Generalizations about the Slope of a Line Positive Slope- Negative Slope Zero Slope- Undefined Slope
Point-Slope Form of the Equation of a Line Example: Find an equation of the line that passes through the point (1, -2) and has a slope of 3.
Sales Prediction During 2004, Nike’s net sales were $12.25 billion, and in 2005 net sales were $13.74 billion. Write a linear equation giving the net sales y in terms of the year x. Then use the equation to predict the net sales for 2006.
Slope-Intercept Form Example: Determine the slope and y- intercept of each linear equation. Then describe its graph. (a) x + y = 2(b) y = 2
Parallel Lines Parallel Lines – Find the slope-intercept form of the equation of the line that passes through the point (2, -1) and is parallel to the line 2x – 3y = 5.
Perpendicular Lines Perpendicular Find the slope-intercept form of the equation of the line that passes through the point (2, -1) and is perpendicular to the line 2x – 3y = 5.
Homework Page , 8-10 even, even, even, 46, odd, 72, 79-82, 85